Tissue cell block



FIG. 1 is a top perspective view of a tissue cell block showing our new design; and,

FIG. 2 is a top plan view thereof, the bottom plan view being a mirror image thereof.

Area depicted in dense stippling represents a species of cells different than the area depicted in sparse stippling. Area depicted in sparse stippling shows a contrasting opaque background. 

CLAIM The ornamental design for a tissue cell block, as shown and described. 